1. Field of the Invention
The present invention relates to a method and system for providing monochrome multi-beam printing with edge enhancement.
2. Description of the Related Art
A wide variety of methods and devices have been proposed for enhancing printing result of text edge, and typical examples include: U.S. Pat. No. 5,029,108 to Lung issued on Jul. 2, 1991; U.S. Pat. No. 5,396,584 to Lee et al. issued on Mar. 7, 1995; and U.S. Pat. No. 5,619,334 to Adams et al. issued on Apr. 8, 1997. Also, a wide variety of methods and devices have been proposed for increasing the scanning and outputting speed of a printer engine, and typical examples include: U.S. Pat. No. 4,733,252 to Daniele et al. issued on Mar. 22, 1988; U.S. Pat. No. 4,823,151 to Miura issued on Apr. 18, 1989; U.S. Pat. No. 4,989,019 to Loce et al. issued on Jan. 29, 1991; U.S. Pat. No. 5,432,535 to Andrews et al. issued on Jul. 11, 1995; U.S. Pat. No. 5,745,153 to Kessler et al. issued on Apr. 28, 1998; and U.S. Pat. No. 5,764,377 to Nacman et al. issued on Jun. 9, 1998. Yet, it is found that the printing result of text edge cannot be improved when using multi-beam technique. The present invention is intended to provide a method and system to solve this problem.
It is a primary object of the present invention to provide a printing control system for providing monochrome multi-beam printing with edge enhancement.
It is another object of the present invention to provide a method for providing monochrome multi-beam printing with edge enhancement.
In accordance with the present invention, a system provides edge enhancement for a printer engine which produces multiple laser beams for marking a corresponding number of scan lines on at least one photosensitive medium. The system comprises:
a window creator means for creating a corresponding number of windows each containing data of a matrix of dots centered at a to-be-processed dot located in a corresponding one of the scan lines;
an edge enhancing device for providing edge enhancement for the windows;
a multiplexer for alternately outputting the windows to the edge enhancing device;
a plurality of modulators each adapted for controlling a corresponding one of the laser beams produced by the printer engine; and
a de-multiplexer for alternately outputting the windows processed by the edge enhancing device to the modulators.
The multiplexer, the edge enhancing device, and the de-multiplexer operate at a frequency two times of that the window creator means and the modulators.
The printer engine may form four scan lines on four photosensitive media, respectively. Alternatively, the printer engine may form at least two scan lines on each of a plurality of photosensitive media.
In accordance with the present invention, a method provides edge enhancement for a printer engine which produces multiple laser beams for marking a corresponding number of scan lines on at least one photosensitive medium. The method comprises the following steps of:
creating a corresponding number of windows each containing data of a matrix of dots centered at a to-be-processed dot located in a corresponding one of the scan lines;
alternately outputting the windows to an edge enhancing device for providing edge enhancement for the windows; and
alternately outputting the windows processed by the edge enhancing device to a plurality of modulators, each said modulator being adapted to control a corresponding one of the laser beams produced by the printer engine.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.